[PATCH 1/2] iommu/iova: introduce iova_magazine_compact_pfns()

[Zhen Lei]

iova_magazine_free_pfns() can only free the whole magazine buffer, add
iova_magazine_compact_pfns() to support free part of it.

Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
---
 drivers/iommu/iova.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index 3e1a8a6755723a9..4b7a9efa0ef40af 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -795,18 +795,19 @@ static void iova_magazine_free(struct iova_magazine *mag)
 	kfree(mag);
 }
 
-static void
-iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
+static void iova_magazine_compact_pfns(struct iova_magazine *mag,
+				       struct iova_domain *iovad,
+				       unsigned long newsize)
 {
 	unsigned long flags;
 	int i;
 
-	if (!mag)
+	if (!mag || mag->size <= newsize)
 		return;
 
 	spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
 
-	for (i = 0 ; i < mag->size; ++i) {
+	for (i = newsize; i < mag->size; ++i) {
 		struct iova *iova = private_find_iova(iovad, mag->pfns[i]);
 
 		BUG_ON(!iova);
@@ -815,7 +816,13 @@ static void iova_magazine_free(struct iova_magazine *mag)
 
 	spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
 
-	mag->size = 0;
+	mag->size = newsize;
+}
+
+static void
+iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
+{
+	iova_magazine_compact_pfns(mag, iovad, 0);
 }
 
 static bool iova_magazine_full(struct iova_magazine *mag)
-- 
1.8.3